But it was actually police who had gained entry to his Christchurch house while he was out – using powers under the Search and Surveillance Act.
They had taken his .22 rifle, 500 rounds of ammunition, and firearms parts after receiving concerns about Bromley's recent behaviour – posting anti-government and anti-mandate videos on social media and protesting against lockdown measures – and his mental health.
It left the 52-year-old founder of the Life Connection Missionary Baptist Fellowship in Christchurch, which belongs to the American Baptist Association USA, feeling targeted because of his political views.
Earlier this month his firearm, and gun licence which was suspended after the night raid, was returned to him by police.
But Bromley says the "abhorrent abuse of power" traumatised his wife and is seeking legal guidance around potential civil action.
"I didn't think that being anti-government or expressing issues about anti-government policies is a reason to question one's sanity," says Bromley who broke lockdown rules last August by hosting a church service at his Avondale home.
"[Police] could've called me, talked to me at any given time – I'd have been happy to talk to them.
"It's absolutely deplorable that they would use such extreme powers on a person who has no criminal history, on such flimsy hearsay [and] without using more traditional measures like a visit or search warrant."
Christchurch barrister and senior firearms lawyer Grant Fletcher fears police are "rampant" and excessive in their use of firearms checks and gun licence revocations.
"The New Zealand Police are hysterical," he says, in the wake of the March 15, 2019 terror attacks on two Christchurch mosques which killed 51 Muslims and resulted in immediate gun law changes.
Police deny allegations of heavy-handedness and say they are operating well within the law.
Under section 18 of the Search and Surveillance Act 2012, police may enter a person's property without a warrant and seize or detain any firearms if they suspect they may have breached the Arms Act, if they believe a person may be incapable of having proper control of the arms or may kill or injure someone, or if there is a protection order against them under the Family Violence Act or there are grounds for one to be sought.
Police launched Operation Tauwhiro in February last year, aiming to crack down on gangs and organised crime groups, and since then have made more than 1500 firearms seizures and 1200 arrests. The nationwide operation has been extended until June 30.
But Fletcher says the crackdown is unfairly targeting lawful owners and the Bromley case is not isolated.
The lawyer cites multiple cases where he has concerns that police have "traumatised and alienated" people by using warrantless searches to remove firearms.
One example, Fletcher says, was a man suffering marriage difficulties. He took his firearms to a friend's place for safekeeping but then had his firearms licence suspended "for telling police what was going on in his life".
A female victim of assault also had her firearms licence revoked, Fletcher says, as did a South Island man who helped a struggling local woman with a bail address, only to be raided by armed police.
In one situation where a person expressed concerns about their own wellbeing and Fletcher says has done "entirely the right thing" by seeking medical help and removing firearms from their property, the police have still turned up and searched their property.
"How is this behaviour by the police encouraging people to work with them?" Fletcher says.
"As the situation now stands, those rushed-through law changes are giving police broad powers to carry out warrantless searches in situations where calm reflection would mean the best thing to do would be for the local cop to pick up a phone and say, 'Hey mate, are you doing alright?'
"Or, 'We're a little bit concerned about something you've said on social media, can we just have a chat with you about it?'
"Instead, they are using such a high level of force that it is completely alienating and traumatising members of the public."
In response to questions from the Herald on Sunday, a police spokeswoman said they were satisfied police were taking "appropriate steps within the legislation to maintain community safety by ensuring firearms only remain in the possession of licence holders who are deemed fit and proper to possess them".
While they refused to comment on specific cases or investigations, in general, police consider warrantless searches on a case-by-case basis, taking into account urgency, the seriousness of any likely offending, risk of harm to members of the public or police, and the likelihood a firearm may be removed or taken to another place before being located or seized by officers.
According to the last New Zealand annual report, police exercised warrantless search powers 19,128 times over the 2020/21 reporting period.